Finally, they could have simply kept track of a kid's balance for their parents, and made a button to send mom and dad a push notification that they would like their money the next time they are together. That probably would have been the most useful of all these things.
They certainly didn't have to let the fact that they couldn't do things exactly as seamlessly as they wanted be a startup killer. I have had this attitude in the past, but then I would look around and discover people doing similar things with great success, using the alternative methods around roadblocks that I had dismissed as unacceptable.
If they really wanted to pursue this project, they could have done it.
[1] https://stripe.com/blog/send-money-to-debit-cards
[2] https://cash.me